'Does things differently'

Michael Loveday, chief executive of Norwich Heritage Economic and Regeneration Trust (Heart) and author of The Norwich Knowledge, said the city was one of the most religious in Europe during the Middle Ages.

As well as dozens of churches, it had six monasteries and a large number of religious hermits, including Julian of Norwich, believed to be the first woman to write a book in English.

"The city also has a massive reputation for religious radicalism," said Mr Loveday.

"I believe Norwich's churches and our other religious groups are also in good health and contribute a huge amount to the life of the city and the countryChloe Smith, Norwich North Conservative MP

Norwich Quakers, including prison reformer Elizabeth Fry and anti-slavery campaigner Thomas Fowell Buxton, also made a great impact he said.

On the census findings, he said: "Norwich always does things in a different way and I'm not surprised it's stuck out of the pack again.

"I don't know what it means, really. It could be that there are still an enormous amount of caring people but they are doing it in a less formal way."

'Huge contribution'

When Chloe Smith, Conservative MP for Norwich North, took her seat in Parliament in 2009, she opted to affirm rather than swear a religious oath of allegiance to the Queen.

"I count myself an atheist and I thought it was far better to be honest about that," she said afterwards.

Of the census, Miss Smith said: "Norwich has always been a non-conformist, independent city so I'm sure people will find this latest statistic very interesting.

"I believe Norwich's churches and our other religious groups are also in good health and contribute a huge amount to the life of the city and the country."

Cookery writer and broadcaster Delia Smith, joint majority shareholder of Norwich City FC, has been a devout Catholic since the age of 22.

She lives in Suffolk but on match days often worships at Norwich's Roman Catholic Cathedral of St John the Baptist.